A new study released in the Journal of Experimental Biology gives some credence to the long held myth that shorter people burn more calories. Scientists have long known that shorter people use up more energy per pound of their body mass when walking than taller people, but the reason has been unclear.
For the purpose of the study, the scientists placed 48 subjects on treadmills. The subjects weighed between 35 and 195 pounds and were between 3.6 to 6 feet in height. They walked on the treadmill at speeds varying from 0.9 miles per hour to 4.3 miles per hour. While they were walking, researchers measured how much oxygen they used in order to calculate their metabolic rate. They also examined the way each subject walked to measure stride length.
The results showed that everyone expended close to the same amount of energy for each stride they took. People with shorter legs take more steps to cover the same distance as people with longer legs, though, and so they found that short people used more energy over a given distance. In other words, tall people use less calories on a per pound basis when they walk because they can take bigger steps.